*Also* - This guide in chessbase format, for use in chessbase and Fritz.
Created by Ivo Fasiori (thanks Ivo, great job!). Click here to download.
This is a summary of the lines following the opening 1.e4 e5 2.Nf3 Nc6 3.d4 exd4 4.Bc4 for the club level player.
This can lead to variations of the Two Knights Defence and the Guicco Piano, as well as the dreaded Max Lange Attack. It is a reasonable choice of opening system for players who thrive on sharp, double-edged positions (a.k.a. cheapo merchants) and it's easy to learn the basic ideas. It's also usually worth a good 15 minutes on the clock in the opening stages, in my experience. I haven't covered everything, but there should be more here than an average club player needs to know.
I've divided it into 3 sections:
Part 1: Black plays 4......Bc5 - Below
Part 2: Black plays 4......Nf6 - probably best
Part 3: Other black 4th moves
1.e4 e5 2.Nf3 Nc6 3.d4 exd4 4.Bc4
Black defends his extra pawn and develops his bishop. He plans Nf6, d6 and castling.
Now black has 3 main options
(a) 5.....dxc3 (b) 5.....d3 (c) 5.....Nf6
Now white gets a free punch
(8.....Qe7 9.Qxc3 Qxe4+ 10.Be3 d6 is often given as being equal, with white having enough compensation for the pawn. Although black's king is exposed and his rook is stuck in the corner for now, it isn't easy for white to generate a convincing attack. However white can gain time by attacking the black queen and has chances. Anyway, if you don't fancy that one there's always the obvious cop-out - 9.Qxe7+ Ngxe7 10.Nxc3 which is dead equal)
Back to the position after 8....d6.
This position has to be o.k. for white, but it'll probably be the better player who wins. To get some idea where white can go from here, the game Sveshnikov-Kupreichik went....
(9.....cxb2 10.Bxb2. When this happens white usually gets a stonking attack)
10.Nxc3 Bxf3 11.gxf3 Qf6 12.f4 Qf7 13.Qb5 Nd4 14.Qd3 Ne6 15.f5 Nc5 16.Qc2 Qc4 17.Be3 Nf6 18.0-0-0 Re8
(18.....Nxe4 19.Rd4 wins a piece)
19.f3 Ncd7 20.Rd4 Qc6 21.Kb1 Re7 22.Qe2 Ne5 23.Bg5 Qc5 24.Rhd1 Nc6 25.Rc4 Qe5 26.Nd5 Rf7 27.Bf4 Qe8 28.Nxc7! Rxc7 29.Bxd6+ Re7 30.e5 Nd7 31.f4 h5 32.Qd3 Rh6 33.Bxe7+ Kxe7 34.Qa3+ Kf7 35.e6+ Rxe6 36.fxe6+ and black soon resigned - A game worth seeing but probably not much use to us club level cloggers.
The other main option is 9.Qxc3, but all the games I could find with this in ended in draws.
This move, suggested by Keene as an antidote to 5.c3, stops white building a pawn center with cxd4 and hinders the knight on b1. That said, white gets a decent game anyway by grabbing queenside space.
(11....axb 12.a6 ba 13.Bd5 Nge7 [13.....Bb7 14.Rxa6 Bxf2+ 15.Rxf2 Rxa6 16.Ng5] 14.Bg5 better for white)
17.Na3 is slightly better for white.
This has transposed to a line of the Guicco Piano.
(6.....Bb6 7.d5 Ne7 8.e5 Ng4 9.d6! is better for white)
(7.....Nxe4 8.Bxb4 Nxb4 9.Bxf7+ - that trick again - Kxf7 10.Qb3+ d5 11.Qxb4 is a bit better for white)
White is happier because his rooks have open files and his knights have good scope.
Part 2: Black plays 4....Nf6
Part 3: Other black 4th moves